SM186     Equality of pressure in all directions     circa 1960     Hydrostatics

  The apparatus can be used to demonstrate that when pressure is applied to a liquid it is transmitted equally in all directions.

  This law, often called Pascal’s law states that:

Pressure  exerted  anywhere upon  a  mass of liquid is transmitted

undiminished   in  all  directions,   and  acts with   the  same  force

on all equal surfaces in a direction perpendicular to these surfaces.

In the apparatus, air is compressed by a plunger and the pressure is transmitted to the water in the four  U  tubes serving as manometers.   The level of the water in these tubes shows that the pressure is transmitted equally in all directions.